The present disclosure relates to a copying machine or a printer or the like including an image forming apparatus.
An image forming apparatus includes a conveying path configured to convey a sheet to an image forming port. The image forming apparatus also includes a mechanism removing (unjamming) a sheet jammed within the conveying path.
For instance, there is a printer including a sheet conveying part (conveying path) of a duplex printing part above a sheet cassette. A sheet guide member is provided so as to be able to open/close under the conveying path. The sheet guide member is lowered to a space from which the sheet cassette has been drawn out. This arrangement makes it possible to remove a jammed sheet. Still further, the sheet guide member is urged to a sheet guide position where the conveying path is closed by a torsion spring. An upper surface of aside plate of the sheet cassette supports the sheet guide member when the sheet cassette is attached to an apparatus body (a space).
The sheet guide member of the printer described above moves automatically to the sheet guide position by a bias force of the torsion spring. However, there is a case when the sheet guide member does not return to the sheet guide position due to a drop of resilience force of the torsion spring. If the sheet is conveyed in this state, jamming occurs again. In order to solve this problem, the abovementioned printer sets the sheet guide member at the correct sheet guide position by attaching the sheet cassette to the printer (the space).
However, the abovementioned printer has a problem that the sheet cannot be conveyed unless the sheet cassette is attached. For instance, the sheet cassette had to attach even if an image is to be formed on a sheet supplied from the manual tray. Therefore, there is a case when user's convenience in use is dropped. Still further, the printer described above is required to provide a device for detecting whether or not the sheet cassette has been attached to the apparatus body. Therefore, there have been problems that the structure of the printer is complicated and it requires extra cost.